The appeal of a wireless communications device lies in its untethered nature. The lack of wires means that the power source for a portable device must be self-contained, so the device's power consumption directly impacts its operating life. Dual power radios exist with at least two communication devices where one communication device, the lower-powered device (LPD), can have a comparatively lower energy capacity than the other communication device, the higher-powered device (HPD). The communication from the LPD to the HPD is an uplink. The communication from the HPD to the LPD is the downlink. The invention can be used with systems where the uplink and downlink happens simultaneously. Additionally, the invention can be used when the uplink and the downlink can occur one direction at a time. In some embodiments, the system consists of a wireless system wherein the LPD has an ultrawideband radio transmitter and a narrowband receiver and the HPD has a NB radio transmitter and an ultrawideband receiver. Communication over the uplink takes place using ultrawideband transmissions, whereas communication over the downlink takes place using narrowband transmission. An ultrawideband radio can be made inexpensively with a transmitter that can consume very little power. The receiver can use a lot of power. A narrowband radio can be made such that the receiver can be made relatively power-efficient, whereas the transmitter consumes a lot of power.
It would therefore be desirable to have a wireless communications device that can: achieve very low power consumption which can extend the operating life of a wireless device; increase the reliability of communications on a wireless link; improve coexistence capability of the wireless communication system; and to accommodate any disparity in the transmission rate in each direction between any pair of communicating devices.